Generac Generator High Engine Temp Alarm — Fix

What it means

Generac High Engine Temp shuts down the generator to prevent engine damage.
Let it cool for 15 minutes, then check cooling airflow, oil level, and cooling fins.

How to Fix It

Let the generator cool

Do not attempt to restart immediately.
Allow the engine to cool for at least 15 minutes.
Restarting a hot engine can cause warping or seizure.
Check for blocked airflow

Air-cooled Generac generators rely on airflow through cooling fins.
Check that the enclosure vents and louvers are not blocked by debris, leaves, snow, or vegetation.
Clean the cooling fins

Inspect the engine cooling fins for a build-up of dirt, grass clippings, or oil residue.
Compressed air or a soft brush can clean between the fins.
Check the oil level and condition

Low oil or oil broken down from overuse cannot lubricate efficiently, causing excess heat.
Check oil level and colour.
Dark or gritty oil needs changing.
Check enclosure clearances

Generac enclosures require specific clearances from walls, shrubs, and structures for adequate airflow.
Refer to your installation manual for minimum clearance distances.
Check the temperature sensor

If the engine feels cool but the alarm persists, the temperature sensor or its wiring may be faulty.
A failed sensor can trigger a false high-temp alarm.

Frequently Asked Questions

Why is my Generac generator overheating?

The most common causes are blocked cooling fins, restricted enclosure ventilation, low oil level, or running the generator at full load in high ambient temperatures.

Can I run my Generac in direct sunlight?

Generac generators are designed for outdoor installation but should be placed with adequate ventilation clearances.
Providing shade while maintaining airflow clearances can reduce heat load in very hot climates.

How do I reset the high engine temp alarm on Generac?

After the engine has cooled and the cause is addressed, press RESET on the control panel.
Return the selector to AUTO and monitor the next exercise cycle.